Photochromic inks are known and exhibit a change in light transmissions or color in response to exposure to ultraviolet radiation. Some photochromic inks exhibit a reversible change in which removal of the incident ultraviolet radiation causes the inks to revert back to their original transmissive state. Numerous photochromic inks have been developed for various product applications over the years, such as security and authenticity labels for documents and color and graphic schemes for product packaging material.
Most, if not all, commercialized photochromic inks are water-based inks, which present printing issues when these photochromic inks are printed in combination with non-photochromic solvent-based inks. For example, wet or semi-wet non-photochromic solvent-based inks that intermingle with wet or semi-wet photochromic water-based inks will breakdown the photochromic pigments, thereby altering or destroying the capabilities of the photochromic inks to change color when exposed to ultraviolet radiation.
Furthermore, packaging material that includes both photochromic water-based and non-photochromic solvent-based inks printed thereon often have “dirty” or unacceptable color and graphic schemes rendering commercially nonviable resulting printed packaging material.
Accordingly, there exists a need to provide improved printed packaging material having color and graphic schemes formed of both photochromic water-based inks and non-photochromic solvent-based inks and suitable methods for manufacturing these printed packaging materials that are capable of ameliorating some or all of the foregoing disadvantages.